The following abbreviations are defined as follows:    CSIM CDMA subscriber identity module    ETSI European Telecommunications Standards Institute    ISIM IP Multimedia Subsystem (IMS) subscriber identity module    MNO mobile network operator    PCF policy control function    RUIM removable user identity module    SCP smart card platform    SIM subscriber identity module    SM subscription manager    USIM universal subscriber identity module
The SIM lock was originally designed to be used with one physical card in a phone where only applications from one operator reside. This card is owned and issued by one operator.
An embedded UICC that can be provisioned by network operators, subscription brokers or subscription managers with a software-based SIM poses new challenges with regard to management. Note that the term software-based SIM (or simply software SIM) also encompasses ISIM; CSIM, USIM. RUIM, etc. In particular, a problem that is presented relates to UICC lifecycle management. The normal lifecycle of a UICC assumes that the UICC is owned by only one operator. Hence if a SIM lock is expired and released, and the SIM becomes unlocked, there is no risk that the SIM lock might be “switched on” again. However a different case is presented in the eUICC environment, where the eUICC is not the property of one particular operator. As a result an operator B could simply switch on the SIM lock again after the SIM lock of operator A has expired. The operator B could also potentially overwrite the SIM lock of operator A.
There possibly could be business scenarios where such a no-change-operator policy is also implemented by operator B, and the user may gain some other benefit(s) not available currently. For example, the user may sign up with a contract from operator B for a defined period of time to obtain a lower cost and/or some other benefit(s).
Reference can be made to International Standard ISO/IEC 7816-4, Identification cards Integrated circuit cards—Part 4: Organization, security and commands for interchange (and to further revisions thereof), in particular to Clause 5.3.3.2 Life cycle status byte:
“The card, files and other objects, each have a life cycle; the life cycle status allows the card and the interface device to identify the different logical security states of the use of the card, files and other objects in the card. To support flexible management of the life cycle as an attribute (see ISO/IEC 7816-9[4]), this clause defines four primary states of the life cycle in the following order.    1) Creation state    2) Initialisation state    3) Operational state    4) Termination state
The life cycle status byte (LCS byte) shall be interpreted according to Table 13.
The values ‘00’ to ‘0F’ are interindustry.
The values ‘10’ to ‘FF’ are proprietary.
TABLE 13Life cycle status byteb8b7b6b5b4b3b2b1Meaning00000000No information given00000001Creation state00000011Initialisation state000001—1Operational state (activated)000001—0Operational State(deactivated)000011——Termination stateNot all zeroxxxxProprietary
Referenced by tag ‘8A’, a file LCS byte may be present in the control parameters of any file (see Table 12).
A card LCS byte may be present in the historical bytes (see 8.1.1.3). Referenced by tag ‘48’, a card LCS byte may be present in EF.ATR (see 8.2.1.1). When it has a MF, the card is in, at least, the creation state.
NOTE Unless otherwise specified, the security attributes are valid for the operational state.”
Another document of interest is SCPREQ(11)0072r14 of ETSI Smart Card Platform Requirement Group (and further revisions thereof) and, in particular, the Annex.
As a general reference one can consult, for example, 3GPP TS 22.022 V10.0.0 (2011-03) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Personalisation of Mobile Equipment (ME); Mobile functionality specification (Release 10). This document describes SIM locking and unlocking in 3GPP.
Reference can also be made to 3GPP TS 31.121 V10.0.0 (2011-04) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; UICC-terminal interface; Universal Subscriber Identity Module (USIM) application test specification (Release 10).
Reference can also be made to 3GPP TS 31.102 V0.1.0 (2011-04) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals. Characteristics of the Universal Subscriber Identity Module (USIM) application (Release 10).
Also of interest herein is Draft ETSI TS 103 383 V<0.0.1> (2011-05), Technical Specification. <Smart Cards; Embedded UICC; Requirements Specification>, (and to further revisions thereof).